Arnica
Arnica Montana
Claim: Relieves aches; an anti-inflammatory and immune enhancer
Why it’s among supplements to avoid: Toxic if it gets inside the body. Taken orally, it’s poisonous unless extremely diluted in homeopathic pill form; applied topically, on unbroken skin, it is generally considered safe. It can cause miscarriages, allergic reactions, paralysis, heart palpitations and death.

Aconite
Aconitum napellus
Claim: Eases joint inflammation, gout, RA
Why it’s among supplements to avoid: It's a strong, fast-acting poison that affects the heart and central nervous system.

Adrenal, spleen, thymus extracts
Claim: Helps fatigue, and relives stress and inflammation
Why it’s among supplements to avoid:
Derived from raw animal organs. The FDA warns those organs could possibly be contaminated.

Autumn crocus
Colchicum autumnale
Claim:
Lessens gout attacks and eases general arthritis
Why it’s among supplements to avoid:
It's a potential poison and should be taken only as a prescription drug (colchicine) under a doctor’s supervision.

5-HTP
5-hydroxytrytophan
Claim: Helps fibromyalgia, sleep disorders and depression.
Why it’s among supplements to avoid:
Associated with esosinophilia myalgia, a serious illness that causes severe rashes, acute pain and other symptoms.

GBL 
Gamma-butyrolactone
Claim: Helps fibromyalgia, sleep problems, depression, claims to “improve sexual and athletic performance and health”
Why it’s among supplements to avoid:
Linked to death, coma and seizures.

L-tryptophan
Claim: Eases sleep disorders and depression
Why it’s among supplements to avoid: Has been associated with esosinophilia myalgia syndrome (EMS), a serious illness that causes severe rashes, acute pain and other symptoms.

Chaparral
Claim: Reduces inflammation
Why it’s among supplements to avoid: May cause hepatitis and kidney and liver damage.

Kombucha tea
Claim:
Helps “rheumatism” and eases pain
Why it’s among supplements to avoid:
Has a high risk of contamination with anthrax and other bacteria.